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    <script>
        var a = 10;
        ++a; //a=11
        var b = ++a + 2; //a = 12  ++a = 12
        console.log(b);//14

        var c = 10;
        c++; //c = 10
        var d = c++ + 2;//c++ = 11 c = 12
        console.log(d);//13

        var e = 10;
        var f = e++ + ++e;// 1.e++ = 10 e = 11   2. ++e =12 e = 12
        console.log(f);//22
    </script>
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